In the related art, a heat source is known, which includes a cooling tower and a cooling water supply device supplying cooling water to a condenser of a chiller. In the field of the heat source system, a technology is suggested, which decreases the power consumption of the cooling water supply device due to need for a reduction in energy consumption.
For example, PTL 1 discloses that a database which indicates relative relationships between an outside wet-bulb temperature, a cooling load, and cooling operations of a cooling tower and a chiller is prepared in advance, and switching between the operations of the chiller and the cooling tower and a control with respect to a cooling water flow rate are performed using the database.